What Are the Signs and Symptoms of Narcolepsy?

The major symptom of narcolepsy is excessive daytime sleepiness with sleep attacks. People with narcolepsy may also have one or more of the following signs and symptoms:

• Sudden loss of muscle tone and control (muscle weakness) over parts or all of the body while awake (cataplexy)
• Sudden inability to move or speak while falling asleep or waking up (sleep paralysis)
• Vivid dreams while falling asleep or waking up (hallucinations)

Daytime Sleepiness

All people with narcolepsy have excessive daytime sleepiness. This is usually the first symptom of the condition. They also may have sudden, irresistible urges to sleep during the day (sleep attacks). They usually fall asleep for just a few seconds or minutes. Rarely, they may fall asleep for as long as an hour or more. Daytime sleepiness can cause:

• Mental cloudiness or “fog”
• Memory problems
• Problems focusing
• Lack of energy
• Depression
• Extreme exhaustion

Cataplexy

Nearly 3 out of 4 people with narcolepsy (75 percent) experience sudden muscle weakness while they are awake. This is called cataplexy, and it is similar to the paralysis that occurs during dream sleep. Mild attacks of muscle weakness can cause:

• Head nodding
  
• Drooping eyelids
  
• Difficulty speaking
  
• Difficulty moving arms or hands or a weakened grip
  
• Buckling of the knees

Severe attacks of narcolepsy may cause complete paralysis and falls. Attacks often last less than 2 minutes, and they may only last a few seconds. During both mild and severe attacks, the person stays fully conscious.

The sudden attacks of muscle weakness in narcolepsy can happen at any time. But these attacks are often triggered by strong emotions, including:

• Laughter
  
• Anger
  
• Fear
  
• Excitement

Attacks of muscle weakness and tone are sometimes the first symptom of narcolepsy that is noticed. But usually this symptom occurs weeks or months after people who have narcolepsy first start to experience excessive sleepiness during the day.

Sleep Paralysis

People with narcolepsy may suddenly not be able to move or speak while falling asleep or waking up. They are fully conscious during these periods of sleep paralysis. The paralysis usually lasts just a few seconds or minutes, but it can be scary. Sleep paralysis is similar to the paralysis that happens in rapid eye movement (REM) sleep. Not all people with narcolepsy have sleep paralysis.

Hallucinations

Some people with narcolepsy have vivid dreams while they are falling asleep, waking up, or dozing. These hallucinations differ from normal dreams because they seem very real and include sights, sounds, smells, tastes, and touch. People with narcolepsy may say these hallucinations are scary like a nightmare. The hallucinations can occur with sleep paralysis.

Other Symptoms

Some people with narcolepsy have difficulty staying asleep through the night. These frequent awakenings may start years after experiencing the first symptoms of narcolepsy. Another symptom of narcolepsy is to carry out certain actions without awareness. This is called automatic behavior. For example, if people with this symptom are writing, they may scribble rather than form words. When driving, people with automatic behavior may get lost or have an accident because of periods when they aren’t aware of what they are doing. People usually do not remember such automatic behavior.